Please help,
My bathroom smells like methane gas. :( It just started today but it is very strong and I have no idea what to do. We checked the vent and ran water down the drains. Please if anyone has any advise for me that would be great.
Kayte

It could be the wax ring used to seal the commode. Without doing a smoke test, and if you have ran water in every drain in the bath, I would start there. I'm sure there are post here about the process of replacing a wax ring if you are not familiar with doing this.

There are also links on the bottom of this page to questions that are similar to yours. It could be that there may be some helpful information in them also.